Measuring the quark and gluon jet energy response in proton-proton collisions at 7 tev center-of-mass energy with the atlas detector

The jet energy scale is one of the largest systematic uncertainties in physics analyses at ATLAS, making it vital to understand and minimize. This thesis provides a comprehensive study of the quark and gluon jet responses, by comparing results of the missing transverse energy projection fraction method in the established gamma+jet events and the newly developed analysis of dijet events. A likelihood discriminator is used to tag jets according to their calorimeter response, and correct the response to one for the dijet study. The mean energy of quark and gluon tagged jets is shown to differ by 4-7%, depending on the energy of the jet.